Cellular building structure

ABSTRACT

A cellular building structure comprised of a multiplicity of cells, each cell in the structure being a substantially fully enclosed unit and having a regular geometric cross-sectional configuration. The cells are situated around and in close proximity to one another with the sides of any one of the cells being at an angle supplementary to a side of another one of the cells, where the supplementary sides are adjacent and parallel to one another to form a compartmentalized cell structure, or where adjacent cells share a common side.

Elite States atent [151 3,688,327

Marshall Sept. 5, 1972 [54] CELLULAR BUILDING STRUCTURE 3,301,149 1/1967Box ..52/615 X [72] Inventor: Rolf R Marshall 2 warremon 3,323,7976/1967 Horton ..52/615 X Court Huntington NY 11743 2,412,778 12/1946Kosek ..52/618 X 2,641,449 6/1953 Antony ..52/236 X [22] Filed: July 27,1970 Primary Examiner.lacob L. Nackenhoff [21] Appl' 58213 Att0rneyLeeC. Robinson, Jr.

[52] US. Cl. ..14/1, 14/19, 52/618 [57] ABSTRACT 3 A cellular buildingstructure comprised of a multiplici- 1 18 6 ty of cells, each cell inthe structure being a substantially fully enclosed unit and having aregular geometric cross-sectional configuration. The cells are situated[56] References cued around and in close proximity to one another withthe TE STATES AT S sides of any one of the cells being at an anglesupplementary to a side of another one of the cells, where 2,745,5205/1956 Boutard ..52/237 the Supplementary sides are adjacent andparallel to 3,529,394 9/1970 Wilklns ..52/618 X one another to form acompartmentalized cell struc ture, or where adjacent cells share acommon side. o e 3,103,025 9/ 1963 Gassner ..14/ 1 8 Claims, 19 DrawingFigures TENTH! SEP 5 I972 SHiEI 1 BF 5 PATENTEDSEP 5 I972 sum 2 or 5OUTFLOW PATENTED SE? 5 I972 SHEET 5 OF 5 CELLULAR BUILDING STRUCTUREBACKGROUND OF THE INVENTION Many structures are sensitive to their ownweight and are limited in their overall size because of the weight ofthe material employed to manufacture the structures. Structures such asbridges, roofs and floor spans, loading ramps, towers, masts, booms,transmission lines, ducts, and others are often limited in their overallsize because of the weight of the material employed to fabricate thestructure. For example, in the case of bridges, a roadway portion of thebridge carries the weight of the vehicles traveling over the bridge. Theroadway is usually supported by a number of towers and support cables.Were it not for these towers and support cables, the weight of theroadway would often be greater than the inherent strength of theroadway, thereby causing the roadway to fall.

Similarly, in radio towers, and the like, the tower should be capable ofsupporting its own weight as well as the weight of the antennas attachedthereto. It is not practicable, in most circumstances, to increase theamount of structural material used to build the tower. This usuallyresults in a commensurate increase in weight. One possibility is toemploy materials having high strength and stiffness properties, and alow weight. However, such materials are rare and when found may often beexcessively expensive.

Structures are usually supported by means of guide cables, supportcables, and support columns, as well as high strength reinforcement. Itis desirable to have structures which are capable of supporting theirown weight with a minimum of external aid from support columns andsupport cables. Certain types of shell structures have been employedsatisfactorily to provide structures having a high strength to weightratio and a high stiffness to weight ratio. For example, many airplanewings comprise a skin of either metal, wood or some other material whichhas been suitably internally stabilized. Such a structure will transmitthe tensile, compressive and shear stresses resulting from loads appliedto the structure without the need of a separate and independent loadcarrying external structure. However, shell structures of this type havenot been readily adaptable heretofore for use in building structures ofthe type to which the present invention is directed.

BRIEF DESCRIPTION OF THE INVENTION The invention relates to a cellularbuilding structure comprising a multiplicity of cells. Each cell has asubstantially regular geometrical cross section. The geometricalconfiguration of the cells is dependent on the number of cells employedand the configuration of the other cells. The cells are situated withrespect to one another with a side of one of the cells being at a firstangle and a side of an adjacent cell being at an angle which issupplementary to the angle of the side of the first cell. The adjacentsides are disposed in close proximity to one another, with the planes ofthe adjacent sides parallel to one another, or else the adjacent cellsshare a common side.

Each one of the cells, when it is used in the structure, is asubstantially totally enclosed structure. The walls of each one of thecells may be composed of a sandwich panel having a light weight coreacting as a stabilizing and strength element and a facing sheet disposedalong either side of the core. The facing sheets may be composed of avariety of materials depending on the desired surface characteristics ofthe sandwich panel.

One variety of structure in which the invention may be employed is inthe building of bridges. A tubular conduit having a hexagonal crosssectional configuration is assembled having each of its six sidesmanufactured from sandwich panels or other light weight substances. Amultiplicity of hexagonal conduits each having a cross sectional areasubstantially similar to the first conduit are disposed parallel to thefirst conduit around its periphery. The hexagonal conduits are situatedwith respect to one another such that selected sides of adjacentconduits form supplementary angles with respect to one another. Thecross section of the overall assembly thus exhibits a honeycombconfiguration.

Each of the hexagonal conduits may have a horizontal running surfacetherein which extends longitudinally of the conduit. The compositehoneycomb conduit assembly is relatively self-supporting and provides astructure having a high strength-to-weight ratio and a highstiffness-to-weight characteristic. The composite structure may beemployed as a bridge, for example, with fewer supports than wouldotherwise be necessary with conventional construction techniques.

It is an object of this invention to provide an improved cellularbuilding structure comprising multiple cellular units which are joinedtogether to supplement one another..

Another object of this invention is to provide a cellular buildingstructure which may be quickly and easily erected at the building siteand is economical to maintain.

It is a further object of this invention to provide a cellular buildingstructure comprising a plurality of hexagonal conduits joined togetherto yield a resultant structure having a high strength-to-weight ratioand a high stiffness-to-weight characteristic.

It is another object of this invention to provide a cellular buildingstructure which may be employed in the design of bridges and similarspanning structures.

It is a further object of this invention to provide a hexagonal conduitstructure having a multiplicity of hexagonal conduits, each hexagonalconduit having a road surface upon which vehicles may travel.

It is a still further object of this invention to provide a hexagonalcellular conduit structure in which the individual hexagonal cellularconduits may be added to one another to form the cellular conduitstructure and provide new road surfaces as the need arises.

It is a further object of this invention to provide a hexagonal cellularconduit structure to form a light weight, stiff, enclosed bridgestructure, having a multiplicity of hexagonal cellular conduits, eachone of the hexagonal cellular conduits having walls which are composedof a honeycomb or other light weight core having facing sheets on eithersurface of the core.

The present invention, as well as further objects and advantagesthereof, will become more fully apparent from the following descriptionof certain illustrative embodiments, when read with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of abridge structure hav ing a number of hexagonal cellular conduitsaccording to one embodiment of the invention.

FIG. 2a is a schematic end view of the conduits as seen from line 2a2aof FIG. 1.

FIG. 2b is a schematic end view similar to FIG. 2a but showing ahexagonal cellular conduit structure according to another embodiment ofthe instant invention.

FIG. 3 is a perspective view, with a portion shown broken away and insection, of one of the walls of a hexagonal cellular conduit accordingto the invention.

FIGS. 4a and 4b are schematic representations similar to FIG. 20 butshowing an air circulation system for the conduits.

FIG. 4c is a diagrammatic perspective view of one of the hexagonalcellular conduits shown in FIG. 1.

FIG. 5 is an enlarged fragmentary view taken along line 5-5 of FIG. 40showing a corner support structure.

FIG. 6a is an enlarged vertical sectional view of one of theinterconnections between adjacent conduits.

FIG. 6b is an enlarged fragmentary sectional view of a representativeinterconnection between two panels of one of the conduits.

FIG. 7a is an enlarged fragmentary sectional view of a tenon joint forsecuring adjacent honeycomb panels which are lying in the same plane toone another.

FIG. 7b is an enlarged fragmentary sectional view of a butt joint forsecuring the ends of adjacent honeycomb panels which are lying in thesame plane.

FIG. 8a is a fragmentary side elevational view of a portion of thebridge structure shown in FIG. ll.

FIG. 8b is an enlarged fragmentary sectional view taken along line8b--8b of FIG. 8a showing one variety of a honeycomb expansion jointwhich may be employed between the panels.

FIG. 9 is a diagrammatic representation of a supported bridge structurein accordance with a further embodiment of the instant invention.

FIG. 10 is an enlarged fragmentary perspective view of a portion of oneof the towers of FIG. 9 showing a transfer structure which may beemployed in conjunction with the cellular tubs.

FIG. 11 is an enlarged fragmentary cross section taken along line 11-11of FIG. 10 showing an expansion joint of the transfer structure.

FIG. 12 is a perspective view of the cellular bridge structure detailinga hanger structure which may be used to support the cellular bridgetube.

FIG. 13 is a perspective view of a cellular tube bridge having a towerspaced framework where the cellular tube forms a compression boom.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS OF THE INVENTIONAs is well known, a bridge is subject to a static gravity load, a liveload, and a load imposed by weather factors. The static gravity load isimposed by the weight of the bridge itself. The live load constitutesthe weight of the vehicles traveling over the bridge and represents aminor proportion of the total load. Conventional truss structuresmanufactured from steel and other heavy weight materials impose atremendous burden on the bridge spans and on the supports for thebridge. By employing a sandwich building material having a core andfacing layers and by joining the sandwiches together in a hexagonalcellular conduit arrangement to form a light weight, enclosed bridgestructure, the static gravity loading is substantially decreased with acorresponding reduction in the necessity for extensive structuralsupport.

Making reference to FIG. 1, there is shown a cellular bridge tube 20comprised of seven hexagonal cellular conduits 22. A number offoundations 24 are distributed along the path of the tube 20. Each ofthe foundations 24 may be made of masonry, steel, concrete or othersuitable material. At least one tower 26 extends upwardly from eachfoundation. The towers 26 are substantially the multiplicity of elementsused in contemporary truss masonry or concrete structures. Furthermore,the total capacity of the tube 20 can be expanded in response to trafficgrowth by the addition of new hexagonal cellular conduits 22 to theinitial cluster of conduits. This permits the original outlay of capitalto be more closely fitted to the existing traffic demand, thusminimizing the period of uneconomical operation, due to overcapacity,which is often experienced in the early years of the operating life of abridge.

As can best be seen in FIG. 2a, a cluster of seven hexagonal cellularconduits 22 is arranged in a substantially cellular array. Each of theconduits 22 is composed of six side panels 34. Because each conduit hasa cross section in the form of a regular, equiangular, equilateralhexagon, adjacent panels 34 meet along their longitudinal edges at aninterior angle of As best seen in FIGS. 10 and 12, when one of theconduits 22 is placed adjacent to a second conduit 22, with one of thepanels 34 of the first conduit in facing contact with one of the panels34 of the second conduit over their entire joint length, the exteriorangle formed by the panels 34 which are adjacent to the facing panels 34is also 120. This permits another hexagonal cellular conduit having aninterior angle of 120 to be situated within the 120 groove thus formed.When, however, adjacent conduits share a common panel (see FIG. 2a theangle between consecutive shared panels is also 120".

In a second cellular configuration shown in FIG. 2b, the cellular bridgetube 20 is composed of four of the hexagonal cellular conduits 22.However, rather than having apexes in the vertical direction, two of theflat panels of each conduit are disposed perpendicular to the verticalaxis. A road surface 32 is defined by a horizontally disposedintermediate panel 54. If desired, a second road surface 35 may beformed by the inner face of the lower of the two panels.

In the arrangement of FIG. 2b two of the hexagonal cellular conduits 22are disposed one above the other in the same orientation. This will forma set of exterior angles between the conduits of 120. Each of theseangles is equal to the interior angle of a third and a fourth hexagonalcellular conduit 22. These latter conduits may be inserted within theexternal angles formed by the first two hexagonal cellular conduits 22.

As can be seen in FIG. 2b, a set of retaining walls 38 are disposedalong the length of the road surface 32.

The retaining walls 38 form an angle of approximately 60 with the roadsurface 32 in the direction of the panel 34 nearest to the retainingwall 38. Therefore, each of the retaining walls 38 forms one leg of anequilateral triangle with the adjacent panel 34 and the adjacent roadsurface 32. The retaining walls 38 provide a safety barrier should a carrun off the roadway 32. The car will rebound from one of the retainingwalls 38 rather than hit one of the panels 34 and possibly injure thestructural configuration of the cellular bridge tube 20. Similar reboundwalls are formed by the sloping panels 34 for the lower road surface 35.

Each panel 34 is comprised of a central core 40 (FIG. 3). A first facingsheet 42 is disposed on one side of the core 40, and a second facingsheet 44 is disposed on the other side, parallel to the first sheet 42.The core 40 is comprised of a multiplicity of tubular elements 46. Eachone of the tubular elements 46 has a central longitudinal axis L in thecenter of the particular tubular element 46 and running the length ofthe tubular element 46. The tubular elements 46 are situated parallel toone another with the central longitudinal axis L of each of the tubularelements 46 parallel to the axis L of each of the other tubular elements46. The tubular elements 46 may be bonded together or fused together.The core may also comprise a foam infrastructure or other suitablestabilizing medium.

The tubular elements 46 may be made from a metal foil, such as aluminumalloy, magnesium alloy or steel, and formed into a honeycomb of cells ofhexagonal, square, triangular, or circular form or a variant or acombination of these shapes. Plastic filament composite or resinimpregnated materials, such as paper or fabric, may be molded into ahoneycomb of cells. The central core 40 acts as a stabilizing element tomaintain the separation between the facing sheets 42, 44. The firstfacing sheet 42 is a sheet of material having a high tension,compression and shear strength. Materials such as steel, aluminum alloy,magnesium alloy, plastic, and composite materials, such as filamentreinforced plastic, filament reinforced metals and resin impregnatedfabrics and papers, may be used for facing sheets.

Although the facing sheet 42 has a high compression, tension, and shearstrength, it may be thin. The strength developed in the panel 34 is dueto the stability influence of the central core 40 which forms the mainthickness of the panel. The first facing sheet 42 is bonded to thecentral core 40 along one of its planar surfaces in a plane transverseto the central longitudinal axis L of each of the tubular elements 46.The second facing sheet 44 is similarly bonded to another face of thecentral core which is also transverse to the central longitudinal axis Lof each of the tubular elements. Thus, the facing sheets are parallel toone another and separated by a distance substantially similar to theheight along the longitudinal axis L of the tubular elements 46.

The first facing sheet 42 and the second facing sheet 44 may be ofsubstantially different materials and have different thicknesses. Forexample, in the cellular arrangement of FIG. 2b, one of the horizontalpanels of the conduits 22 serves as a road surface 32. Therefore, one ofthe facing sheets 42 which is used on the panel should be of a materialhaving a high resistance to wear. The other facing sheet on that panelwill be facing downwardly and will be exposed to little wear and only toambient conditions. Therefore, the second facing sheet 44 may be of alighter material and may be of a material which does not have as high acompressional, tensile and shear strength as the material used on thefirst facing sheet 42.

The central core 40, and particularly the individual tubular elements 46of the central core 40, support and stabilize the first or inner facingsheet 42 and the second or outer facing sheet 44. The facing sheets 42and 44 transmit tensile, compressional and shear loads acting on thefacing sheets in the plane of the sheets. The adhesive bond for fusingthe facing sheets and the core should be capable of transmitting thesetensile, compressional and shear loads so that the sandwich willfunction as an integral unit. This will help in minimizing prematureelastic instability failure arising in the panel 34 in the form ofbuckling due to tension waves and crippling under compressional waves.

The panel 34 behaves like a basically solid panel of the same overallthickness, but with a much reduced weight due to the low density core.

Six panels 34 are arranged to abut edgewise to form the hexagonalcellular conduits 22 through which the bridge traffic can pass. A numberof the conduits 22 are joined together in a cluster to form the cellularbridge tube 20. The number of conduits which are joined together isdependent on the traffic flow which needs to be accommodated.

Because the cellular bridge tube 20 comprises a number of enclosed roadsurfaces 32, it is preferable to provide exhaust and ventilation meanswithin the tube, particularly with respect to the centrally locatedhexagonal cellular conduits 22.

A ventilation system is provided in each of the hexagonal cellularconduits 22 which provides a flow of air through that conduit.Ventilation openings 48 (FIG. 4c) are located at spaced intervals alongthe abutting edges of the panels 34 of each conduit. The ventilationopenings 48 have duct work (not shown) leading to a central ventilationduct system, As can best be seen in FIGS. 4a and 4b, there is provided amultiplicity of ducts, generally labeled 52, which communicate betweenthe atmosphere outside of the cellular bridge tube 20 and theventilation openings within the conduits 22. As traffic passes along theroad surfaces 32 within each one of the conduits, the traffic creates aflow of air through each conduit. This flow of air tends to create apartial vacuum behind the moving vehicle and set up currents which drawcool air from the outside (as can be seen from the solid lines in FIGS.4a, 4b and 4c). As the air becomes hotter and filled with noxious fumes,it will tend to rise within each one of the conduits 22. This will placethe air in contact with the upper ventilation openings 48 which willallow it to exit from the conduit to the outside. As the cellular bridgetube 20 is increased in size, it may be desirable to substitute apumping system for forcing air into the various conduits rather thanrely on the current set up by the flow of traffic.

A hexagonal cell provides a suitable cross sectional shape toaccommodate vehicles. In the cellular arrangement shown in FIG. 2a andFIG. 5, each of the conduits 22 is provided with a road surface 32. The

road surface 32 is formed on the a road panel 54 positioned between twononconsecutive edges of the lowermost panels 34 of each conduit. Theroad panel 54 is horizontal and spans the width of the cell.

As best shown in FIG. 5, there is an open space between the outer facingsheets 44 on adjacent panels 34, while the inner facing sheets 42 are incontact. The space between the outer sheets is closed by a bridgingpanel 56 which spans the distance between the adjacent sheets 44. Twoangle members 58 are respectively situated on the facing ends of eachpair of adjacent panels 34. Each of these angle members is affixed toboth the bridging panel 56 and the panel 34 along their entire length.

The bridging panel 56 is comprised of a central core 40b (FIG. 6b). Thecentral core may comprise a multiplicity of tubular elements or maycomprise a foam infrastructure. An inner facing sheet 42b and an outerfacing sheet 44b are bonded to the inner and outer surfaces of thecentral core 40b. The facing sheets 42b and 44b are parallel to oneanother and parallel to a plane which is transverse to the centrallongitudinal axis of the tubular elements of the bridging panel.

A set of angles '74 join the outer facing sheet 44 of the panels 34 tothe outer facing sheet 441) of the bridging panel 56. The angles runalong the abutting edges of the facing sheets. The angles 74 may bebonded to the outer facing sheets, or may be secured by conventionalmeans, such as rivets.

The road panel 54 has a central core 400, an upper facing sheet 42a anda lower facing sheet 44a (see FIG. The road surface 32 is disposed abovethe upper facing sheet 42a. Light-weight roadways may be employed, suchas crystalized silica, or sand added to a surfacing resin which bonds tothe upper facing sheet. This type of treatment yields a highlyattractive paving about one-fourth inch thick with wearing qualitiescomparable to several inches of much heavier concrete or bituminousmaterials.

A roadway support girder 60 extends longitudinally intermediate each endportion of the roadway panel 54 and the panel 34 therebeneath. Thegirder 60 is affixed to the lower facing sheet of the roadway panel 54and to the upper sheet of the panel 34. The girders 60 support theroadway panel 54 to prevent it from being displaced in the horizontaldirection.

An angularly extending side wall, generally labeled 62, is disposedalong the lateral extremities of the roadway panel 54- where the roadwaypanel 54 contacts the cellular conduit panels 34. The side wall 62 iscomprised of a facing sheet 64 and a crushable filler material 66intermediate the facing sheet 64 and the panel 34. If a vehicle shouldhappen to slide off of the road surface 32, it will hit the side wall62, and rather than damage one of the panels 34 it will crush thecrushable filler material 66, thereby absorbing the primary force of theimpact.

A hinge 68 is situated at the abutting inner facing sheets 42 of thepanels 34. The hinge 68 serves as a panel joint to connect the innerfacing sheets 42 of the panels 34. The area beneath the roadway panel 54is available for services and ducts.

The triangulated joints formed when the edges of three panels 345 abutform areas of great rigidity. These triangulated joints, combined withthe stiff sandwich panels 34, result in a structure which is relativelystiff under bending and torsion loads. The triangulated joints are bestshown in FIG. 6a. In FIG. 6a, three panels 34 having longitudinal edgesE come together such that the edges E form a triangulated joint.

A closing section 70 is secured to the ends of each one of the panels 34to form the edge E. The closing section is intermediate the inner sheet42 and the outer sheet 44 of the panel and encompasses the central core40. The closing section protects the central core from injury andstiffens the edges of the panel. A continuous angle or hinge 72 isaffixed to the sides which abut one another along the longitudinal edgeE. The hinges may be fused to the outer surfaces of the facing sheets ormay be secured to the outer surfaces of the facing sheets by means ofconventional bolt or other fastening arrangements.

The panels 34 may be of a great length and can even be of a length equalto the distance to be spanned. However, the panels will usually be of ashorter length. This necessitates joining panels 34 along the length ofthe conduit.

One such joint is a tenon joint, as best illustrated in FIG. 7a. Thistenon joint is useful for securing panels together which lie in the sameplane. Doubler plates 78 are affixed to the inner surfaces of the innerfacing sheets 42 and the outer facing sheets 44 of the panels to bejoined. The doubler plates are coterminous with the ends of the panelsand extend parallel to the facing sheets from the ends thereof into thecore material 40 for a length P.

A closing section 70 encompasses the central core and extends outwardlyfrom the end of the panel 34a. The closing section 70 protrudes into thecore material and is disposed adjacent the upper and lower doublerplates 78. A closing section 71 encompasses the central core of thepanel 34b and is adjacent to both of the doubler plates 78. A set ofmechanical fasteners 76 join the inner and outer facing sheets and thedoubler to the closing section of the first panel 34a.

A second type of transverse panel joint is shown in FIG. 4b. This typeof panel joint, referred to as a butt joint, includes a first doublerplate 78 bonded to the inner side of the inner facing sheet 42 and asecond doubler plate bonded to the inner side of the outer facing sheet44, of each of the panels to be joined. Each doubler plate isintermediate one facing sheet and the central core. The doubler platesextend from the end of the respective facing sheets 42, 44 inwardly adistance D. A closing section 7th is bonded to the end of the centralcore of each panel. The closing section 70 has a frontal edge 75 whichis parallel to the central longitudinal axis of the tubular elements 46of the central core. The frontal edge is coterminous with the ends ofthe doubler plates and the ends of the inner and the outer facingsheets.

An L bracket 7 is secured to the outer surface of the inner facing sheet42 and the outer surface of the outer facing 44 of each of the panels34a and 34b. One leg of the U bracket is parallel and adjacent to therespective facing sheets 42, 44, while the other leg of the L bracket isparallel to and in the same plane as the frontal edge 75. The L bracketsare secured to the panels 34a, 34b, by means of mechanical fasteners 76which pass through the L" brackets and into the panels. A second set ofmechanical fasteners 80 are passed through the facing legs of the Lbrackets to secure the first panel 34a to the second panel 34b.

Provision is made for expansion and contraction of the cellular bridgetube 20. In particular, a variety of transfer structures may be employedto allow sections of the cellular bridge tube to be joined and toaccommodate expansion joints between the sections of the cellular bridgetube 20. In FIG. 80, there is shown a cellular bridge tube supported bya foundation 24 of masonry and a tower 26 of prestressed concrete orsteel. The tower 26 is mounted on the foundation 24 and extends upwardlytherefrom. A cradle 82 is located at the uppermost extremity of thetower 26. The cradle 82 has an upper surface 84 which has aconfiguration which supplements the outer peripheral configuration ofthe cellular bridge tube 20. Two sections 20a and 20b of the cellularbridge tube 20 are slidably mounted on the cradle 82. Connector panels85 are disposed intermediate the two sections of the bridge tube. Theconnector panels are rigidly affixed to the individual conduit panels inone of the sections and are slidably situated within the conduit panelsin the second sectron.

The interconnections between the panels can best be seen in FIG. 8b. Oneof the panels 340 in the first section 200 has a core structure 400. Thecore structure is provided with a U" shaped recess along the edge of thepanel which accommodates a closing section 70 and a set of slide walls88. A set of end closing sections 90 is disposed intermediate the facingplates and the slide walls.

The corresponding panel 34d in the second section of the tube has asimilar configuration. However, the closing section 70 has been omittedfrom the panel 34d, and the facing plates 88a are somewhat shorter thanthe plates 88.

The connector panel 85 is comprised of a central core 92 and a set ofparallel facing sheets 94 and 96 disposed parallel to one another andtransverse to the central longitudinal axis of the central core 92. Thedistance between the outer surfaces of the facing sheets 92 and 94 issubstantially similar to the distance between the inner surfaces of theslide walls 88 and 880. A set of connector closing sections 86 is bondedto the ends of the connector panel 85 intermediate the facing plates 04and 96 and coterminous therewith. The section 86 on the left end of thepanel 85 is disposed in spaced relationship with the section 70.

One end of the connector panel 85 is rigidly secured within the U shapedcavity of the panel 34d. The other end of the connector panel 85 isslidably situated within the U shaped cavity formed in the panel 34c.The panels 34c and 34d are separated by a distance I and may expand andcontract without changing the overall length of the cellular bridge tube20. Expansion dams (not shown) may be employed between the roadwaypanels to compensate for expansion in the individual panels. Variousexpansion devices may be employed with and are within the scope of theinstant invention.

The concept of this invention may be applied in a number of types ofbridges. For example, as can be seen in FIG. 1, the cellular bridge tube20 may be employed in a pier supported bridge. A relatively short tomedium span of bridge tube is supported at intervals by towers topped bycradle structures. At either end of the tube, the conduits are separatedfrom one another and form approach ramps, or exit ramps. Expansionjoints as well as roadway expansion dams are provided, as necessary, atthe tower and cradle structures, as is shown in FIG. 8a.

A second type of bridge is the suspension bridge, as is best illustratedin FIG. 0. The suspension bridge comprises a long central span ofcellular bridge tube 20 suspended from a network of catenary cables 100.Hanger cables 102 extend downwardly from the catenary cables 100 and aresecured to the outer periphery of the cellular bridge tube 20. Thecatenary cables 100 are in turn supported by two towers, generallylabeled 104. The tube passes through each one of the towers 104 througha transfer structure 106 situated within each tower. A set of anchorcables 108 is located between each tower and the shore. One end of eachof the anchor cables is secured to the uppermost portion of the tower104, and the other end of the same anchor cable 108 is secured to ashore anchor 110. The majority of the torsion and lateral loads, andsome of the local vertical loads over the center span of the cellularbridge tube 20, are transmitted to the towers 104 at either end of thecenter span of the cellular bridge tube 20. The loads are transmitted atthe point where the tube meets the towers (FIG. 10). The transfercollars 106 pass the load. Each collar has an inner peripheralconfiguration substantially similar to the external peripheralconfiguration of the tube adjacent to the tower.

As can best be seen in FIG. 11, the collars 106 within the towers 104also accommodate expansion joints between the individual panels 34. Aset of rollers 112 is located intermediate each collar 106 and the outerfacing sheets 44 of the conduits. Other low friction means may beemployed, such as a fluid film or a coated surface. As the sections ofthe tube expand and contract, the length differential is taken up by themotion of the connector panel which slides within the panels of the tube20. The expansion and contraction of the roadway panel is accommodatedfor by an expansion dam as in the case of the pier bridge.

The cellular bridge tube 20 is attached to the hanger cables 102 of thesuspended bridge structure by means of a set of hanger brackets 114 (seeFIG. 12). Each one of the hanger brackets 114 is affixed to the outerportion of a vertical side of one of the conduits. Mechanical fasteners116, such as rivets or the like, secure the hanger brackets 1 14 to thevertical surfaces. A transfer bolt 118 connects the hanger cable 102 tothe upper extremity of the hanger bracket 114. The hanger brackets 114are distributed along the entire span of the cellular bridge tube 20.

The catenaries may be eliminated in certain applications, and the hangercables 102 may be employed directly between the top of the towers 104and the hanger brackets 114 to provide direct cable support. Othervariations are within the knowledge of those skilled in the art.

Referring now to FIG. 13, there is shown a variety of unsupported bridgespan. This variety of bridge is often employed to span a relativelylarge distance. The bridge is composed of a cluster of conduits actingin conjunction with a space framework, generally labeled 120. In thisarrangement, the cellular bridge tube forms the top or a compressiveboom 122 of the bridge. A tension boom 124 is supported from thecompressive boom 122 by means of the space framework. A number ofcompressive struts 126 are disposed between the compressive boom 122 andthe tension boom 124. The compressive struts 126 are provided with a setof stabilizing cross members 128. A set of stabilizer cables 130 isdisposed between the top and the bottom of each compressive strut 126,and each cable is connected to the corresponding stabilizing crossmember 128.

Each of the stabilizing cross members 128 also serves as an expander tospread the stabilizer cables 130. Diagonal ties 132 run from the pointswhere the compressive struts 126 connect with the compressive boom 122to the tension boom 124. The hexagonal cellular conduits 22 are eachprovided with a roadway panel 54 having a road surface 32 over whichvehicles may travel. An upper surfacing layer 134 may be applied overall of the hexagonal cellular conduits 22 to provide a smooth uppersurface and protect the outer facing sheets 44 of the hexagonal cellularconduits 22. This forms another variety of enclosed cellular bridge tube20.

In all cases, it is to be understood that the above describedarrangements, in particular the materials to be used as core structuresand facing sheets and the particular application to bridge construction,are merely illustrative of a particular embodiment to the many possibleapplications of the principle of the invention. Numerous and variedother arrangements in accordance with these principles may readily bedevised by those skilled in the art without departing from the spiritand scope of the invention.

What is claimed is:

l. A cellular building structure comprising a multiplicity of hexagonalcells secured to one another in a honeycomb arrangement, a pair ofbridge towers, a transfer collar disposed within and extending througheach said bridge tower and supported by said tower for transmitting loadfrom one side of the tower to the other, said cellular buildingstructure being disposed within and extending through said transfercollar, and a multiplicity of cables supported by said bridge towers tosupport the length of said cellular building structure.

2. A cellular building structure according to claim 1 wherein all ofsaid cells have substantially the same cross-sectional area and whereinthe cross-section of each cell forms a regular equilateral hexagon.

3. A cellular building structure according to claim 1 which furthercomprises roadway means within each of said cells for dividing the cellinto a pentagon and a triangle and wherein said roadway means issubstantially horizontal.

4. A cellular building structure according to claim 1 wherein each ofsaid cables is affixed to the outer surface of one of the hexagonalcells of said cellular building structure.

5. A cellular building structure comprising a multiplicity of hexagonalcells secured to one another in a honeycomb arrangement, at least onebridge tower, a transfer collar disposed within and extending throughsaid bridge tower, said cellular building structure being disposedwithin and extending through said transfer collar, a multi licity ofcables disposed between the uppermost pom on said bridge tower and saidcellular building structure to support the length of said cellularbuilding structure, a plurality of expansion joints, one for each ofsaid hexagonal cells, positioned within said transfer collar, saidtransfer collar having an inner periphery substantially similar to theouter periphery of said cellular building structure, and a low frictionmeans disposed intermediate said inner surface of said transfer collarand said outer periphery of said cellular building structure.

6. A cellular building structure according to claim 5 wherein said lowfriction means comprises a set of rollers capable of motion in adirection parallel to the length of the cellular building structure.

7. A cellular building structure according to claim 5 wherein said lowfriction means comprises a fluid film having a low coefiicient offriction.

8. A cellular building structure comprising a multiplicity of conduits,each of said conduits having a cross section substantially equal to anequilateral hexagon, a road surface disposed within each of saidconduits to divide the conduits cross section into a pentagon and atriangle, said road surface being substantially horizontal, a tensionboom disposed parallel to and below said cellular building structure,and a multiplicity of compressive struts interconnecting said structureand said tension boom.

1. A cellular building structure comprising a multiplicity of hexagonalcells secured to one another in a honeycomb arrangement, a pair ofbridge towers, a transfer collar disposed within and extending througheach said bridge tower and supported by said tower for transmitting loadfrom one side of the tower to the other, said cellular buildingstructure being disposed within and extending through said transfercollar, and a multiplicity of cables supported by said bridge towers tosupport the length of said cellular building structure.
 2. A cellularbuilding structure according to claim 1 wherein all of said cells havesubstantially the same cross-sectional area and wherein thecross-section of each cell forms a regular equilateral hexagon.
 3. Acellular building structure according to claim 1 which further comprisesroadway means within each of said cells for dividing the cell into apentagon and a triangle and wherein said roadway means is substantiallyhorizontal.
 4. A cellular building structure according to claim 1wherein each of said cables is affixed to the outer surface of one ofthe hexagonal cells of said cellular building structure.
 5. A cellularbuilding structure comprising a multiplicity of hexagonal cells securedto one another in a honeycomb arrangement, at least one bridge tower, atransfer collar disposed within and extending through said bridge tower,said cellular building structure being disposed within and extendingthrough said transfer collar, a multiplicity of cables disposed betweenthe uppermost point on said bridge tower and said cellular buildingstructure to support the length of said cellular building structure, aplurality of expansion joints, one for each of said hexagonal cells,positioned within said transfer collar, said transfer collar having aninner periphery substantially similar to the outer periphery of saidcellular building structure, and a low friction means disposedintermediate said inner surface of said transfer collar and said outerperiphery of said cellular building structure.
 6. A cellular buildingstructure according to claim 5 wherein said low friction means comprisesa set of rollers capable of motion in a direction parallel to the lengthof the cellular building structure.
 7. A cellular building structureaccording to claim 5 wherein said low friction means comprises a fluidfilm having a low coefficient of friction.
 8. A cellular buildingstructure comprising a multiplicity of conduits, each of said conduitshaving a cross section substantially equal to an equilateral hexagon, aroad surface disposed within each of said conduits to divide theconduit''s cross section into a pentagon and a triangle, said roadsurface being substantially horizontal, a tension boom disposed parallelto and below said cellular building structure, and a multiplicity ofcompressive struts interconnecting said structure and said tension boom.